It's a completely overlooked bit of functionality in Freon that only a few players seem aware of. So many times in overtime I've tried to get someone's attention (to give them HP or raise my own) by pinging a single link bullet or raising the shield but ppl just aren't aware of it.
IF YOU STAND NEXT TO A LIVE TEAMMATE, YOUR HP WILL RISE TO MATCH THEIRS, OR VICE VERSA
This can be pivotal in overtime and change the course of the round:
If you see a teammate that is obviously low health, stick close to them for a few secs to give them a HP boost.
If someone has just thawed you, then hang around a for a few seconds to let them up their HP by standing close.
In a very short amount of time you can go from most team members having nearly zero HP to all having full HP.